Pseudoporphyria

Pseudoporphyria

Clinical presentation of pseudoporphyria on the skin.

Pseudoporphyria is a skin condition that mimics the symptoms of porphyria, a group of disorders caused by abnormalities in the chemical steps leading to the production of heme. Unlike true porphyria, pseudoporphyria does not involve the accumulation of porphyrins in the body.

Clinical Features

Pseudoporphyria is characterized by skin changes that resemble those seen in porphyria cutanea tarda, the most common form of porphyria. These changes include:

• Photosensitivity: Increased sensitivity to sunlight, leading to skin damage.
• Blistering: Formation of blisters on sun-exposed areas, particularly the dorsal surfaces of the hands and feet.
• Scarring: Healing of blisters may result in scarring and milia formation.
• Fragile skin: The skin may become fragile and easily damaged.

Causes

Pseudoporphyria can be induced by several factors, including:

• Medications: Certain drugs, such as nonsteroidal anti-inflammatory drugs (NSAIDs) and antibiotics, have been implicated in the development of pseudoporphyria.
• Dialysis: Patients undergoing hemodialysis for chronic kidney disease may develop pseudoporphyria.
• Ultraviolet light exposure: Excessive exposure to UV light can trigger the condition.

Diagnosis

The diagnosis of pseudoporphyria is primarily clinical, based on the characteristic skin findings and the absence of porphyrin accumulation. Laboratory tests may be performed to rule out true porphyria, including:

• Urine porphyrin analysis: To check for elevated levels of porphyrins.
• Blood tests: To assess liver function and rule out other causes of skin photosensitivity.

Treatment

Management of pseudoporphyria involves:

• Avoidance of triggering factors: Discontinuation of causative medications and protection from UV light.
• Sun protection: Use of broad-spectrum sunscreens and protective clothing.
• Wound care: Proper care of blisters to prevent infection and promote healing.

Prognosis

The prognosis for pseudoporphyria is generally good, especially when the triggering factors are identified and managed appropriately. The skin lesions may resolve over time with proper care and avoidance of further triggers.

Related Pages

• Porphyria
• Photosensitivity
• Blistering skin conditions